QQuestion
(a) Define specific resistance.
(b) What happens to the specific resistance of a conductor if its length is doubled?
(c) Name a substance whose specific resistance remains almost unchanged with the increase in its temperature.
Exam-ready answer • 03 Mark
✓Answer
(a) Specific resistance is the resistance of a wire of that material having unit length and unit area of cross-section.
(b) It remains unchanged because specific resistance is independent of the dimensions of the conductor.
(c) Manganin.
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